JP6306342B2 - Cellulose ester composition - Google Patents

Description

  The present invention relates to a cellulose ester composition.

Since cellulose esters such as cellulose acetate generally have poor thermoplasticity, they are usually used as a composition containing a plasticizer.
Patent Document 1 is an invention relating to a fatty acid cellulose ester-based resin composition, and describes that a known plasticizer can be blended (paragraph number 0023).
Patent Document 2 is an invention relating to a resin composition composed of a cellulose ester having an average substitution degree of 2.7 or less, a plasticizer, and a filler. As a plasticizer, it is described that phosphate ester etc. can be used (paragraph number 0020). In the examples (Table 1), an example in which talc, wollastonite or glass fiber is blended as a filler is shown.

JP-A-10-306175 JP-A-2005-194302

  The present invention provides a cellulose ester composition having a high fluidity, good mechanical properties, and a molded article having good wet heat stability.

  The present invention provides a cellulose ester composition containing (B) 5 to 40 parts by mass of a plasticizer and (C) 0.5 to 10 parts by mass of dipentaerythritol with respect to 100 parts by mass of (A) cellulose ester. .

  The cellulose ester composition of the present invention has high fluidity, and the molded product obtained from the composition of the present invention has good mechanical properties and good wet heat stability.

<(A) component>
The cellulose ester of component (A) used in the composition of the present invention is a known one, and examples thereof include cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, and cellulose acetate butyrate.
Other examples include polycaprolactone-grafted cellulose acetate, acetyl methyl cellulose, acetyl ethyl cellulose, acetyl propyl cellulose, acetyl hydroxyethyl cellulose, acetyl hydroxypropyl cellulose, and the like.

The cellulose ester as the component (A) is preferably cellulose acetate having an average substitution degree of 2.7 or less.
(A) As for the polymerization degree of the cellulose ester of a component, a viscosity average polymerization degree becomes like this. Preferably it is 100-1000, More preferably, it is 100-500.

<(B) component>
The plasticizer of the component (B) used in the composition of the present invention is a known one.
As the plasticizer of the component (B), for example, one kind selected from the following plasticizers can be used, two or more kinds can be used in combination, and commercially available products other than the following are also used. be able to.
Aromatic carboxylic acid esters [dimethyl phthalate, diethyl phthalate, dibutyl phthalate, dihexyl phthalate, dioctyl phthalate, di-2-ethylhexyl phthalate, etc. C 1-6 Alkyl C 1-12 Alkyl Esters such as C 1-6 Alkyl C 1-12 Alkyl Esters, Phthalates, C 1-12 Alkyl Aryl-C 1-3 Alkyl Esters such as Butyl Benzyl Phthalate 6 alkylphthalyl C2-4 alkylene glycolate, trimethyl trimellitic acid, triethyl trimellitic acid, trioctyl trimellitic acid, trimellitic acid tri C1-12 alkyl ester, pyromellitic acid tetraoctyl such as trimellitic acid tri-2-ethylhexyl Such as Pyromellitic acid tetra C1-12 alkyl ester etc.],
Fatty acid esters [Adipic acid esters such as dibutyl adipate, dioctyl adipate, butoxyethoxyethyl benzyl adipate, dibutoxyethoxyethyl adipate, azelaic acid esters such as diethyl azelate, dibutyl azelate, dioctyl azelate, sebacic acid Dibutyl, sebacic acid esters such as dioctyl sebacate, butyl oleate, methylacetyl ricinoleate, etc.]
Among them, adipic acid ester or a mixture of adipic acid ester is preferable.
Lower fatty acid esters of polyhydric alcohols (such as glycerin, trimethylolpropane, pentaerythritol, sorbitol) [such as diglycerin tetraacetate],
Glycol esters (such as dipropylene glycol dibenzoate),
Citrate esters such as acetyltributyl citrate,
Amides [N-butylbenzenesulfonamide, etc.]
Ester oligomers (such as caprolactone oligomers),
Other examples include phosphoric esters such as triphenyl phosphate which are also used as flame retardants.
The plasticizer as the component (B) is preferably selected from aromatic carboxylic acid esters and fatty acid esters.

  (B) Content of a component is 5-40 mass parts with respect to 100 mass parts of (A) component, Preferably it is 5-35 mass parts, More preferably, it is 10-30 mass parts.

<(C) component>
The content of dipentaerythritol as the component (C) used in the composition of the present invention is 0.5 to 10 parts by mass, preferably 1 to 10 parts by mass with respect to 100 parts by mass of the component (A). More preferably, it is 2-8 mass parts.

<(D) component>
The composition of the present invention may further contain a thermoplastic elastomer containing (D) component (meth) acrylic acid alkyl ester units.
In the present invention, “(meth) acrylic acid” is used to include both acrylic acid and methacrylic acid.
As the thermoplastic elastomer of component (D), (D-1) a thermoplastic elastomer having a core-shell structure or (D-2) a thermoplastic elastomer having a block copolymer structure can be used.

  As the component (D-1), a core-shell structure graft copolymer in which a monomer containing a (meth) acrylic acid alkyl ester constituting the shell is graft-polymerized with respect to the rubber-like polymer constituting the core is preferable.

As a rubbery polymer constituting the core,
Polyalkyl acrylate rubbers such as butadiene rubber, isoprene rubber, polybutyl acrylate, poly (2-ethylhexyl acrylate), butyl acrylate / 2-ethylhexyl acrylate copolymer;
Silicone rubbers such as polyorganosiloxane rubber;
Butadiene-acrylic composite rubber, IPN composite rubber composed of polyorganosiloxane rubber and polyalkylacrylate rubber, styrene-butadiene rubber, ethylene-α olefin rubber (ethylene-propylene rubber, ethylene-butene rubber, ethylene-octene rubber, etc.), Examples thereof include ethylene-acrylic rubber and fluorine rubber. These can use 1 type (s) or 2 or more types. Among these, butadiene rubber and polyalkyl acrylate rubber (acrylic rubber) are preferable.
The (meth) acrylic acid alkyl ester is preferably methyl methacrylate or methyl acrylate.

As the component (D-1), methyl methacrylate-butadiene copolymer (MB), methyl methacrylate-acrylic rubber copolymer (MA), methyl methacrylate-acrylic-butadiene rubber copolymer, and the like are preferable.
As the component (D-1), a commercially available product can be used. For example, “Paraloid (registered trademark) EXL-2602” (core / shell made of butadiene-methyl methacrylate copolymer, manufactured by Rohm and Haas Co., Ltd.) Type graft copolymer), EXL-2603 (core / shell type graft copolymer comprising polybutadiene / alkyl acrylate / alkyl methacrylate copolymer), EXL-2633 (polybutadiene / alkyl acrylate / alkyl methacrylate) And a core / shell type graft copolymer made of a copolymer).

(D-2) As the thermoplastic elastomer having a block copolymer structure, a block (Tg100 to 120 ° C.) composed of (meth) acrylic acid methyl ester units and a block composed of (meth) acrylic acid butyl ester units (Tg− 40 to -50 ° C) is preferable.
As the component (D-2), a commercially available product can be used, and examples thereof include “KULARITY (registered trademark) LA-2250” (block copolymer type) manufactured by Kuraray Co., Ltd.

  (D) As for content of a component, 1-30 mass parts is preferable with respect to 100 mass parts of (A) component, 1-20 mass parts is more preferable, and 1-15 mass parts is further more preferable.

The composition of this invention can contain a well-known thermoplastic resin according to a use.
Known thermoplastic resins include styrene resins such as ABS resin and AS resin, polycarbonate resins, polyolefin resins such as polyethylene and polypropylene, polyamide resins such as polyamide 6, polyamide 66, polyamide 610, and polyamide 612, and acrylic. Resin, methacrylic resin, polyester resin, polyacetal resin, polyphenylene sulfide resin and the like.
40 mass% or less is preferable in the total amount with the cellulose ester of (A) component, and, as for the content rate of a well-known thermoplastic resin, 20 mass% or less is more preferable.

The composition of the present invention may further contain a filler.
Examples of the filler include fibrous fillers and non-fibrous fillers (powdered or plate-like fillers). For example, in paragraphs 0025 to 0032 of Patent Document 2 (Japanese Patent Laid-Open No. 2005-194302) Mention may be made of those described.
As for the content rate of a filler, 5-50 mass parts is preferable with respect to 100 mass parts of cellulose ester of (A) component, More preferably, it is 5-40 mass parts, More preferably, it is 5-30 mass parts.

  The composition of the present invention includes an epoxy compound described in paragraph Nos. 0035 to 0042 of Patent Document 2 (Japanese Patent Laid-Open No. 2005-194302), an organic acid, a thioether, a phosphite compound described in paragraph Nos. 0043 to 0052, and the like. The stabilizer may be contained.

  Depending on the application, the composition of the present invention may contain conventional additives such as other stabilizers (for example, antioxidants, ultraviolet absorbers, heat stabilizers, light stabilizers, etc.), colorants (dyes, Pigments, etc.), antistatic agents, flame retardant aids, lubricants, antiblocking agents, dispersants, fluidizing agents, anti-dripping agents, antibacterial agents and the like.

The composition of the present invention may be prepared by, for example, mixing each component in a dry or wet manner using a mixer such as a tumbler mixer, a Henschel mixer, a ribbon mixer, or a kneader.
Furthermore, after premixing with the mixer, a method of kneading with an extruder such as a single-screw or twin-screw extruder to prepare pellets, or a method of melting and kneading with a kneader such as a heating roll or a Banbury mixer is applied. can do.

  The composition of the present invention can be molded into various molded products by injection molding, extrusion molding, vacuum molding, profile molding, foam molding, injection press, press molding, blow molding, gas injection molding and the like.

  The composition of the present invention includes, for example, each part in the OA / home appliance field, the electrical / electronic field, the communication field, the sanitary field, the transportation vehicle field such as an automobile, the housing-related field such as furniture and building materials, the miscellaneous goods field, It can be used for a housing or the like.

Examples and Comparative Examples Using a Henschel mixer, each composition was stirred and mixed so that the frictional heat in the mixer was 70 ° C or higher, and then a twin screw extruder (cylinder temperature: 200 ° C, die temperature: 220 ° C). And extruded to pelletize.
The obtained pellets were supplied to an injection molding machine, and a test piece was injection molded under the conditions of a cylinder temperature of 210 ° C., a mold temperature of 50 ° C., and a molding cycle of 30 seconds (injection 15 seconds, cooling time 15 seconds), Used for each evaluation test.

<Use ingredients>
Component (A) Cellulose acetate 1: manufactured by Daicel Corporation, trade name “L50”, substitution degree 2.5, viscosity average polymerization degree 180
Cellulose acetate 2: manufactured by Daicel Corporation, trade name “L20”, substitution degree 2.5, viscosity average polymerization degree 140
(B) Component Adipic acid ester plasticizer: DAIFACTY-101, manufactured by Daihachi Chemical Industry Co., Ltd. (C) Component dipentaerythritol: Dipentarit, manufactured by Guangei Chemical Industry Co., Ltd. (D) Component (D- 1) “Paraloid (registered trademark) EXL-2602” (core / shell type graft copolymer made of butadiene-methyl methacrylate copolymer), Stabilizer component (1) Phosphite compound manufactured by Rohm and Haas : ADK STAB 2112, manufactured by ADEKA Corporation (2) Epoxy compound: Celoxide 2021P, manufactured by Daicel Corporation (3) Citric acid: citric acid (anhydrous), manufactured by Kishida Chemical Co., Ltd.

<Measurement test>
(MFR)
The measurement was performed at 220 ° C. and a load of 10 kg.
(Tensile strength)
Based on ISO527, the tensile strength of the test piece was measured (tensile strength unit: MPa).
(Bending strength / flexural modulus)
It was measured according to ISO178 (unit: MPa).

(Mass reduction rate under wet heat conditions)
The test piece (90 × 50 × 3 mm) obtained by injection molding was measured for mass (W1) after leaving it in an atmosphere of 65 ° C. and 85% RH for 48 hours, and mass (W2) after being left for 500 hours. The mass reduction rate ((W1-W2) / W1 × 100) was calculated.
In addition, before performing mass measurement, the mass measurement was performed after wiping off the component adhering to the test piece. It shows that wet heat stability is so good that a mass reduction rate is small.

From Example 1 and Comparative Example 1, the fluidity (MFR) can be maintained at a high level by using the component (B) and the component (C) in combination, and further the mass under mechanical strength and wet heat conditions. The reduction rate was also maintained at a high level.
From the comparison between Example 2 and Comparative Example 2, the fluidity and mechanical strength were maintained at a high level by making the total amount of the component (B) and the component (C) about the same as the component (B). The mass loss rate under wet heat conditions could be maintained at a high level.
From the comparison between Example 3 and Comparative Example 3, by using the component (B) and the component (C) in combination, it is possible to maintain the fluidity, mechanical strength, and mass reduction rate under wet heat conditions at a high level. did it.

Claims (4)

(A) For 100 parts by mass of cellulose ester,
(B) 5 to 40 parts by mass of an adipate ester plasticizer,
(C) A cellulose ester composition containing 0.5 to 10 parts by mass of dipentaerythritol.   Furthermore, the cellulose-ester composition of Claim 1 which contains 1-30 mass parts of thermoplastic elastomers containing a (meth) acrylic-acid alkylester unit as (D) component.   The cellulose ester composition according to claim 1 or 2, wherein the cellulose ester as the component (A) is selected from cellulose acetate, cellulose ester acetate propionate, and cellulose acetate butyrate.   The cellulose ester composition according to any one of claims 1 to 3, wherein the cellulose ester as the component (A) is a cellulose acetate having a substitution degree of 2.7 or less.